A parking lock device for a motor vehicle is provided for preventing, in an actuated condition, the motor vehicle from rolling away. Generally, the parking interlock gear is arranged on a torsionally stiff input or output shaft. For example, in the case of an electric drive device for a motor vehicle, the parking interlock gear is arranged on a rotor shaft of the electric drive machine. The drive device usually interacts with a transmission device.
When the parking lock device is actuated, for example, on a hillside and in the towing operation of the motor vehicle, in order to interlock the drive train, the drive train winds up, due to the partially low component rigidity of the components located in the drive train and due, as well, to the transmission ratio step of the transmission device. Consequently, an elastic deformation of the components located in the drive train takes place. During the actuation of the parking lock device in order to disengage the parking lock, the drive train abruptly relaxes, wherein the parking pawl rattles on the parking interlock gear when the actuator system does not release the interlock between the parking pawl and the parking interlock gear rapidly enough. This is the case, in particular, when a disengagement speed of an interlocking element actuating the parking pawl is too low. The rattling causes high dynamic loads and impermissible wear on the components of the parking lock device. Wear results in changes in function-relevant component geometries and friction faces of the parking lock device. Furthermore, wear negatively influences the latching speeds, the power transmission capacity, the service life, the rattling characteristics, as well as the engagement and disengagement characteristics of the parking lock device. The abrupt relaxation of the drive train causes the drive train to swing in both directions of rotation and, therefore, causes the parking interlock gear to rotate in both directions of rotation. The oscillation amplitude decreases over time.
DE 10 2010 042 917 A1 describes a parking lock device for a motor vehicle. The parking lock device includes a parking interlock gear including teeth and tooth gaps, as well as a parking pawl including a ratchet tooth. The parking interlock gear executes a turning motion having a rotation angle and a rotational speed about an axis of rotation and the parking pawl executes a swiveling or pivoting motion having a swivel range and a swivel speed about a swivel axis. The swivel axis is arranged in parallel to the axis of rotation. Above a predefined engaging speed, the parking pawl is deflected by the teeth of the parking interlock gear and thereby undergoes an oscillating swiveling motion, a so-called rattling. The parking interlock gear and the parking pawl are kinematically linked to each other via a linear relation between the swivel range and the rotation angle while the tooth tips of the two components are in contact.
A parking lock device for a motor vehicle that, in particular, reduces the contact forces and the wear between the parking interlock gear and the parking pawl in a targeted rotational speed range would therefore be advantageous.